The Reagan administration's dogfight with Libyan warplanes and summit talks with Israel's prime minister could boost Soviet policy aims in the Mideast, diplomats here say.
The top Kremlin priorities seem to be to complicate United States efforts to piece together an anti-Soviet coalition in that strategically important region and to counter a heightened US military profile there.
If commentary by the official Soviet news media is any indication, Moscow entertains no serious hope of an early improvement in relations with such key Mideast actors as the Israelis, the Egyptians, and the Saudi Arabians.
The latest thunderclap in the Soviets' stormy relations with Egyptian President Anwar Sadat came Sept. 14, with the charge by an authoritative Cairo newspaper that Moscow was plotting to topple him.
And the recently announced friendship pact linking Libya and Ethiopia with Saudi Arabia's militantly pro-Soviet neighbor, South Yemen, would seem likely to encourage traditional Saudi mistrust of the men in the Kremlin.
As for Israel, Prime Minister Menachem Begin said after talks in Washington with President Reagan that the two countries had agreed on widened security cooperation to counter "a special threat: Soviet expansionism."
That still nonspecific accord could complicate Mr. Reagan's bid to consolidate ties with key moderate Arab regimes, which habitually argue that Israel threatens them at least as much as Moscow does.
If any such complications do arise, diplomats here suggest, the Soviets will be indirect beneficiaries of the Reagan-Begin summit.
The official Soviet news agency wasted little time in declaring that the strategic understanding reached in Washingtion posed a "direct threat . . . above all to the Arab countries of the [Mideast] region."
The Kremlin may also gain from developments in US relations with a distinctly nonmoderate Arab state: Libya.
Libyan strong man Col. Muammar Qaddafi, although long a major customer for sophisticated Soviet weaponry, has never qualified as a full ally of the Kremlin.
Neither the nor the Kremlin really trusts each other. Soviet officials acknowledge privately that the mercurial colonel would not seem the most reliable of potential Mideast partners, despite his welcome "antiimperialism." Colonel Qaddafi, for his part, has traditionally preached a fervently Islamic brand of nonalignment that dictated distance from both superpowers.
Some Moscow diplomats suspect that the US-Libyan dogfight over the Mediterranean in August, in which two Libyan warplanes were downed, may change this. Colonel Qaddafi and other Libyan officials have hinted as much in recent public statements.
If this proves to be so, the shift could include the erosion of Colonel Qaddafi's longstanding reluctance to extend formal access rights for Soviet ships and soldiers to bases in Libya.